Micrometer gauges



Sept 10, 1957 4 Q zELNiCK 2,805,483

' MICROMETER GAUGEs Filed Nov. 23, 1953 IN V EN TOR.

ATTORNEYS Patented Sept. 10, 1957 MICROMETER GAUGES Charles Zeinick, Saginaw, Mich., assigner to Ehe Lufkin Ruie Company, Saginaw, Mich.

Application November 23, 1953, Serial No. 393,781

7 Claims. (Cl. 'S3-164) This invention relates to micrometer gauges in general, and more particularly to a novel and improved stop means which is actuated to feed the spindle into engagement with the work, and which automatically ceases feeding the spindle and simply revolves when the spindle and anvil are properly engaging the work so that the measurement can be read.

As is well known, the feel associated with the use of micrometers or similar measuring devices, or the point at which the user feels the work is properly engaged by the device and that reading should be taken, varies with the individual, unless he takes a large number of readings per day. Consequently, there are often inaccuracies in the readings because the spindle and anvil are engaging the Work with either too much or too little pressure when the readings are taken, relative to the engaging pressure at which the device was calibrated.

One of the prime objects of my invention is to provide means associated with the spindle of a gauge, which can be actuated to feed the spindle to the work until the work is engaged with a predetermined pressure, whence rotation of the spindle will cease, regardless of the continued action of said means, thus eliminating the necessity of relying on the feel of the individual using the device, and insuring uniformity and accuracy of measurement.

A further object of the invention is to design means for rotating the spindle which ceases feeding the spindle when a predetermined measuring pressure is attained, thereby preventing the overfeeding of the spindle with consequent wear and/or damage to the work-contacting surfaces of the micrometer.

Another object of the invention is to design means for feeding the spindle of a micrometer to the work and which ceases rotating the spindle when the spindle is locked in engagement with said work, thus providing a gauge which remains in adjusted position until a reading can be taken.

With the above and other objects in view, the present invention consists in the combination and` arrangement of parts, hereinafter more fully described, illustrated in the accompanying drawing, and more particularly pointed out in the appended claims, it being understood that changes may be made in the form, size, proportion and minor details of construction, without departing from the spirit, or sacrificing any of the advantages of the invention.

In the drawing:

Fig. l is a side elevational view of a micrometer showing my improved actuating collar thereon.

Fig. 2 is a part sectional, side elevational view of the clamping member and actuating collar mounted on the end of the micrometer sleeve.

Fig. 3 is a part sectional, side elevational View of the actuating collar only.

Fig. 4 is a transverse sectional view taken on the line 4-4 of Fig. 2.

Referring now more particularly to the accompanying drawing wherein I have shown a micrometer of the general design illustrated and described in Patent No. 2,212,910 with my improved mechanism incorporated therein, the micrometer includes a frame 10 provided with an anvil 11, and a tubular barrel 12 inscribed with a longitudinal scale 13 projects from the frame 10 and is interiorly threaded at its outer end to receive the threaded outer end of a spindle 14 as usual.

A tubular sleeve 15 is telescoped over the inscribed barrel 12, the outer end of said sleeve being internally threaded as shown to receive the threaded end (not shown) of the spindle 14, which projects beyond the barrel 12. The outer end portion of the sleeve 15 is knurled as at 16, and the opposite end is Ibeveled and bears a circumferential scale 17 which cooperates with the longitudinal scale 13 in the conventional manner.

Formed on the extreme end of the sleeve 15 is a sectored or split portion 1S of reduced diameter, including a threaded portion 19, and a tapered nose portion 20. A clamping member 21 includes a reduced outer threaded end 22 and a knurled cap 23 is mounted thereon and is interiorly threaded as at 24, the member 21 being bored with a cooperating taper as at 25 to accommodate the nose portion 2G and clamp the split outer end of the sleeve 15 on the projecting threaded end of the spindle 14. In this manner, the rotating sleeve 15 and clamping member 21 are clamped to the gauging spindle 14 and when actuated, serve to feed the spindle 14 into engagemeut with the work in the usual manner.

This particular structure is more specifically illustrated and described in previously-mentioned Patent No. 2,212,910, and I do not deem it necessary to describe it in greater detail. The structure dealt with to this point is common to applicants assignees micrometers, and it is the improvement hereinafter described to which this preent application is directed.

The instant improvement includes a knurled collar 26 seated on a shouldered portion 27 provided by reducing the diameter of the clamping member 21, a certain amount of clearance 28 being provided between the shouldered portion 27 and collar 26. Formed in the portion 27 is an annular groove 29 in which is seated a friction coil spring 36 having only a few convolutions, the one end of the spring being bent radially inwardly as at 31 so as to be accommodated in the radial passage 32 formed in the wall of the member 21. Thus, the friction spring 30, which is of greater diameter than the internal diameter of collar 26 and exerts a uniform pressure against the internal Wall of the collar 26 over the length of the spring opposes relative rotation of the collar 26 and member 21 is anchored in position and cannot become disengaged.

The cap end 23, of course, serves to prevent the collar 26 from slipping ofIr the end of the clamping member 21, and is readily disengageable to allow removal of the collar 26 to replace the spring 3G after prolonged use or for any other purpose.

In practice, the collar 26 is grasped between the thumb and forefnger and rotated or twirled to feed the spindle 14 into engagement with the work to be measured. When a predetermined setting is attained, the knurled collar 26 will overcome the opposition of the spring 39 and rotate relative to the clamping member 21 instead of further feeding the spindle 14 into the work. At this point, the user must exercise considerably more force to revolve the collar 26 and is then aware that the spindle is locked in measuring position, and that the gauge is ready to be read. The user is thus prevented from inadvertently further actuating the spindle 14 and possibly damaging the gauge measuring surfaces and Work, and taking an inacandjth'ere is little possibility of grit gettingin betweenthespring and Wallandclogging the action. Any dirt which. might accumulate over along period ofl use is easily dis lodged'by moving the cap assembly through a propercleaning solvent.

It will thus be seen that I`have perfectedY a very simpler and improved automaticA stop means for protecting the Work and the gauge contact surfaces from undue clamp ing strains, and for locking the gauge at the. same setting whenever it is used, thusinsuring greater accuracy of` measurement. Further, the` friction spring pan/lof the instant device is so anchored that it cannot be pulled loose and thus render thestop mechanismV inoperative.

It is obviousfthat the instant means also assures that the tubular sleeve can be set at the truetzero when the spindle is brought, into engagement with the anvil to calibrate the gauge asdetermined by the point at which the knurled collar 26 begins to rotate relative to the clamping member 21.

From the foregoing description, it will be apparent that I have perfected a very simple, practical and inexpensive automatic stop means formicrometer gauges and the like.

What I claim is:

l. In a micrometer gauge, the combination with the measuring spindle and the split end sleeve therefor, of an annular tubular clamping member for clamping the split end of the actuating sleeve on the measuring spindle, saidv clamping member having an annular groove therein, an actuating collar freely revolvable on said clampingl member, and an annularcfriction spring comprisingV a wire of annular cross section Wound in side by side. convolutions of greater diameter than the diameter of said collar so as to exert a pressure thereagain'st disposed in said groove to maintain said collarand clamping member in rotative, frictional engagement in the absence of counteractive endwise pressure on the spindle opposing rotation thereof.

2. In a micrometer gauge the combination with the measuring spindle thereof and an annular member normally clamped thereon, of an actuating collar having an internal diameter greater than the diameter of said member, an annular friction spring comprising a Wire of substantially annular cross section wound in side by side convolutions of'greater diameter than the internal diamter of said collar, said convolutions being of equal diameter and exerting a uniform pressure against the internal Wall of Ithe actuating collar overY the length of the spring,

and means for preventing endwise movement of saidY spring when the collar is 4twisted and has relative rotation withV said member because of a counteractive endwise pressure on the spindle opposing further rotation thereof.

3. The combination defined in claim 2 in Whichone end of said spring is bent radially inwardly and a radial passage is provided in the Wall of said member to receive .l 41 spring comprising a wire of generally annular cross section wound in side by side convolutions of greater diameter than the internal diameter of said collar, said convolutions exerting a pressure against the internal Wall of the actuating collar over substantially the length of the spring;

and means for preventing endwise movement of said spring when the collar is twistedfand has relative rotation with said surface because of a counteractive endwise pressure on the said.one of: thevspindle assembly and barrel on which saidfcollar-,is mounted-opposing furtherrotation thereof.

5. In a micrometer gauge or the like; the combination with the relatively rotatable and axially: adjustable barrel and spindle assembly thereof; of, anV` actuating collar,

mounted on a surface of one of'said barrel and spindle assembly, having an internal diameter greater than the diameter of said surface; a generally annular friction spring comprising a Wire Wound in side by side convolutions'of greater external diametercthan the internal diameter of'saidcollar, saidjconvolutions exertingpa pressure against the internal wallv of the actuatingcollar over sub"- stantially the length ofthe spring; .and means for preventing endwise movement of saidspring lWhen the collar is twisted and has relative rotation with said member because of a counteractive endwise pressure on the said one of the spindle assembly and b'arrel'orr which said collar is mounted opposing further rotationthereof,

6. In a micrometer gauge or the like; thecombination with the relatively rotatable andtaxially adjustable barrel and measuring spindle assembly thereof; of an actuating collar mounted'on an exposed annular surface of said spindle assembly having an internal diameter greater than the diameter of said member; an annular friction spring comprising awire wound in sidev by side convolutions of greater diameter thanjthe internal diameter of said collar; said convolutionsbeingof substantially equalV diameter and exerting a pressure againstthe internal wall of the actuating collar over substantially the length of the spring, and means for preventing endwise movement of said spring when the collar` is Vtwisted andY has relative rotation. with said memberA because of; av counter-active endwise` pressure on the spindle assembly opposing further rotation thereof.

7. In a micrometer gauge or the like; the combinationV Y with the relatively rotatable andy axially, adjustable barrel and spindleV assembly thereof; ofl an;y actuatingY collar, mounted on a surface of ,one of'said, barrel and spindle assembly, having an internal diameter greater than theV References Cited in the tile of this patent UNITED STATES PATENTSV 350,513- Washburn c Oct.' 12,1886- 2,533,973 sterkt-2315....y Dec.` 12, 1950,v 2,665,490 Zelnick Jan. 12,1954 

